The invention relates to a carbon brush for electric fuel pumps.
In electric fuel pumps installed near the fuel to be pumped, fuels of relatively high viscosity, in particular diesel fuels, result in the problem that rotation of the commutator draws a layer of fuel between the commutator and the carbon brush. The carbon brush floats to the surface due to the resulting increase in banking-up pressure between the carbon brush and the commutator or collector and the fuel film. Contact between carbon brush and commutator is significantly reduced and increased wear on the entire commutation system--including both carbon brushes and commutator--may result.